The percentage of Americans without health insurance dropped slightly to 15.4 percent in 2012, according to an annual report issued today by the U.S. Census Bureau.

That's down from 15.7 percent in 2011.

But the number of people without health insurance totaled 48 million -- not statistically different than 2011's 48.6 million.

So is health care reform working? The fairest answer is it's too early to tell, given that many of the law's provisions aimed at increasing coverage -- new insurance marketplaces for individuals and small businesses, and coverage mandates for individuals and larger employers -- haven't kicked in yet.

But the share of people covered by private health insurance -- 63.9 percent -- was statistically the same as in 2011. So was the shared covered by Medicaid -- 16.4 percent. The growth in coverage came from Medicare -- from 15.2 percent in 2011 to 15.7 percent in 2012. That's due to demographics, not health care reform.

Uninsured rates declined for children younger than 18, but there was no statistical change for other age brackets -- including the 19-25 range. That's notable because health care reform allowed young adults to remain on their parents' insurance plans until age 26. So it looks like this provision isn't being used as much as expected.

The bureau also found that real median household income remained statistically unchanged at $51,017. It had declined the previous two years.

The poverty rate also didn't budge much -- it's 15 percent, meaning 46.5 million Americans live at or below the poverty line. The poverty rate is 2.5 percentage points higher than it was in 2007, the year before the financial crisis sent the economy into a recession.

"The good news from today’s 2012 income and poverty results is that for the first year since the great recession hit, things aren’t getting worse," writes Jared Bernstein, a former economic adviser to President Barack Obama. "The bad news is that three years into an economic recovery, they're not getting better either."